   * {
       margin: 0;
       padding: 0;
       box-sizing: border-box;
       font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
   }

   :root {
       --primary: #3498db;
       --secondary: #2c3e50;
       --success: #2ecc71;
       --warning: #f39c12;
       --danger: #e74c3c;
       --dark: #1a1f2a;
       --light: #f8f9fa;
       --card-bg: #252d3a;
       --sidebar-width: 250px;
       --header-height: 70px;
   }

   body {
       background-color: #1a1f2a;
       color: #e9ecef;
       min-height: 100vh;
   }

   #app {
       display: flex;
       min-height: 100vh;
   }

   /* 侧边栏样式 */
   .sidebar {
       width: var(--sidebar-width);
       background-color: var(--dark);
       height: 100vh;
       position: fixed;
       padding-top: 20px;
       box-shadow: 3px 0 10px rgba(0, 0, 0, 0.2);
       z-index: 100;
   }

   .logo {
       padding: 20px;
       text-align: center;
       border-bottom: 1px solid #2c3e50;
       margin-bottom: 20px;
   }

   .logo h1 {
       font-size: 1.5rem;
       color: #fff;
       display: flex;
       align-items: center;
       justify-content: center;
       gap: 10px;
   }

   .logo i {
       color: var(--primary);
   }

   .nav-links {
       list-style: none;
       padding: 0 20px;
   }

   .nav-links li {
       margin-bottom: 10px;
   }

   .nav-links a {
       display: flex;
       align-items: center;
       padding: 12px 15px;
       color: #b0b3b8;
       text-decoration: none;
       border-radius: 5px;
       transition: all 0.3s ease;
       gap: 12px;
   }

   .nav-links a:hover,
   .nav-links a.active {
       background-color: var(--card-bg);
       color: #fff;
   }

   .nav-links a i {
       width: 25px;
       text-align: center;
   }

   /* 主内容区样式 */
   .main-content {
       flex: 1;
       margin-left: var(--sidebar-width);
       padding: 20px;
   }

   /* 顶部导航栏 */
   .topbar {
       display: flex;
       justify-content: space-between;
       align-items: center;
       background-color: var(--card-bg);
       padding: 15px 30px;
       border-radius: 10px;
       margin-bottom: 30px;
       box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
   }

   .search-box {
       display: flex;
       align-items: center;
       background: #1e2430;
       padding: 8px 15px;
       border-radius: 30px;
       width: 300px;
   }

   .search-box input {
       background: transparent;
       border: none;
       color: white;
       padding: 8px;
       width: 100%;
       outline: none;
   }

   .user-actions {
       display: flex;
       align-items: center;
       gap: 20px;
   }

   .notification,
   .user-profile {
       position: relative;
       cursor: pointer;
   }

   .notification i {
       font-size: 1.2rem;
   }

   .badge {
       position: absolute;
       top: -5px;
       right: -5px;
       background: var(--danger);
       color: white;
       border-radius: 50%;
       width: 18px;
       height: 18px;
       font-size: 0.7rem;
       display: flex;
       align-items: center;
       justify-content: center;
   }

   .user-profile img {
       width: 40px;
       height: 40px;
       border-radius: 50%;
       object-fit: cover;
   }

   /* 统计卡片 */
   .stats-container {
       display: grid;
       grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
       gap: 20px;
       margin-bottom: 30px;
   }

   .stat-card {
       background: var(--card-bg);
       border-radius: 10px;
       padding: 25px;
       display: flex;
       flex-direction: column;
       box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
       transition: transform 0.3s ease;
   }

   .stat-card:hover {
       transform: translateY(-5px);
   }

   .stat-card.daily {
       border-top: 4px solid var(--primary);
   }

   .stat-card.monthly {
       border-top: 4px solid var(--success);
   }

   .stat-card.total {
       border-top: 4px solid var(--warning);
   }

   .stat-card.users {
       border-top: 4px solid var(--danger);
   }

   .stat-header {
       display: flex;
       justify-content: space-between;
       align-items: center;
       margin-bottom: 15px;
   }

   .stat-title {
       font-size: 1rem;
       color: #b0b3b8;
       font-weight: 500;
   }

   .stat-icon {
       width: 40px;
       height: 40px;
       border-radius: 8px;
       display: flex;
       align-items: center;
       justify-content: center;
       font-size: 1.2rem;
   }

   .stat-icon.daily {
       background: rgba(52, 152, 219, 0.2);
       color: var(--primary);
   }

   .stat-icon.monthly {
       background: rgba(46, 204, 113, 0.2);
       color: var(--success);
   }

   .stat-icon.total {
       background: rgba(243, 156, 18, 0.2);
       color: var(--warning);
   }

   .stat-icon.users {
       background: rgba(231, 76, 60, 0.2);
       color: var(--danger);
   }

   .stat-value {
       font-size: 2rem;
       font-weight: 700;
       margin-bottom: 5px;
   }

   .stat-change {
       display: flex;
       align-items: center;
       font-size: 0.9rem;
       color: #b0b3b8;
   }

   .stat-change.positive {
       color: var(--success);
   }

   .stat-change.negative {
       color: var(--danger);
   }

   .red-text {
       color: var(--danger);
       /* 使用你定义的主题色，如 #e74c3c */
   }

   .no-data {
       font-size: 0.9rem;
       display: flex;
       align-items: center;
       gap: 8px;
   }

   /* 图表区域 */
   .charts-container {
       display: grid;
       grid-template-columns: 2fr 1fr;
       gap: 20px;
       margin-bottom: 30px;
   }

   .chart-card {
       background: var(--card-bg);
       border-radius: 10px;
       padding: 25px;
       box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
   }

   .chart-header {
       display: flex;
       justify-content: space-between;
       align-items: center;
       margin-bottom: 20px;
   }

   .chart-title {
       font-size: 1.2rem;
       font-weight: 600;
   }

   .chart-actions {
       display: flex;
       gap: 10px;
   }

   .chart-actions button {
       background: #1e2430;
       border: none;
       color: #b0b3b8;
       padding: 5px 10px;
       border-radius: 5px;
       cursor: pointer;
       transition: all 0.3s;
   }

   .chart-actions button:hover,
   .chart-actions button.active {
       background: var(--primary);
       color: white;
   }

   .chart-container {
       height: 300px;
       position: relative;
   }

   .loading-overlay {
       position: absolute;
       top: 0;
       left: 0;
       right: 0;
       bottom: 0;
       background: rgba(0, 0, 0, 0.7);
       display: flex;
       align-items: center;
       justify-content: center;
       z-index: 10;
       border-radius: 10px;
   }

   .loading-spinner {
       width: 40px;
       height: 40px;
       border: 4px solid rgba(255, 255, 255, 0.3);
       border-radius: 50%;
       border-top: 4px solid var(--primary);
       animation: spin 1s linear infinite;
   }

   @keyframes spin {
       0% {
           transform: rotate(0deg);
       }

       100% {
           transform: rotate(360deg);
       }
   }

   .refresh-btn {
       background: var(--primary);
       color: white;
       border: none;
       padding: 10px 20px;
       border-radius: 30px;
       cursor: pointer;
       display: flex;
       align-items: center;
       gap: 8px;
       margin: 20px auto;
       transition: all 0.3s;
   }

   .refresh-btn:hover {
       background: #2980b9;
       transform: scale(1.05);
   }

   /* 响应式调整 */
   @media (max-width: 992px) {
       .charts-container {
           grid-template-columns: 1fr;
       }
   }

   @media (max-width: 768px) {
       .sidebar {
           width: 70px;
       }

       .logo h1 span,
       .nav-links a span {
           display: none;
       }

       .logo h1 {
           justify-content: center;
       }

       .nav-links a {
           justify-content: center;
       }

       .main-content {
           margin-left: 70px;
       }

       .search-box {
           width: 200px;
       }
   }

   @media (max-width: 576px) {
       .stats-container {
           grid-template-columns: 1fr;
       }

       .topbar {
           flex-direction: column;
           gap: 15px;
       }

       .search-box {
           width: 100%;
       }
   }